Category Archives: Human Reproduction

DUBLIN--(BUSINESS WIRE)--

Research and Markets (http://www.researchandmarkets.com/research/whnkxx/textbook_of_assist) has announced the addition of the "Textbook of Assisted Reproductive Techniques: Clinical Perspectives" book to their offering.

Textbook of Assisted Reproductive Technologies has become a classic comprehsive reference for the whole team at the IVF clinic. The fourth edition comes more conveniently as a set of two separate volumes, one for laboratory aspects and the other for clinical applications.

The text has been extensively revised, with the addition of several important new contributions on clinical applications, including new chapters on lifestyle factors, tailored ovarian stimulation, frozen-thawed embryo transfer, viral disease, and religious perspectives. As before, methods, protocols, and techniques of choice are presented by eminent international experts.

Key Topics Covered:

Introduction to Third Edition. Robert Edwards: The path to IVF. IX Quality Management Systems

- Quality management in reproductive medicine. X Patient Investigation and the Use of Drugs

- Lifestyle, periconception, and fertility.

- Indications for IVF treatment: from diagnosis to prognosis.

- Initial investigation of the infertile couple.

More here:
Research and Markets: Textbook of Assisted Reproductive Techniques: Clinical Perspectives

Public release date: 20-Jun-2012 [ | E-mail | Share ]

Contact: Karthika Muthukumaraswamy karthika@siam.org 267-350-6383 Society for Industrial and Applied Mathematics

Philadelphia June 20, 2012Malaria affects over 200 million individuals every year and kills hundreds of thousands of people worldwide. The disease varies greatly from region to region in the species that cause it and in the carriers that spread it. It is easily transmitted across regions through travel and migration. This results in outbreaks of the disease even in regions that are essentially malaria-free, such as the United States. Malaria has been nearly eliminated in the U.S. since the 1950s, but the country continues to see roughly 1,500 cases a year, most of them from travelers. Hence, the movement or dispersal of populations becomes important in the study of the disease.

In a paper published this month in the SIAM Journal on Applied Mathematics, authors Daozhou Gao and Shigui Ruan propose a mathematical model to study malaria transmission.

"Malaria is a parasitic vector-borne disease caused by the plasmodium parasite, which is transmitted to people via the bites of infected female mosquitoes of the genus Anopheles," says Ruan. "It can be easily transmitted from one region to another due to extensive travel and migration."

The life cycle of plasmodium involves incubation periods in two hosts, the human and the mosquito. Therefore, mathematical modeling of the spread of malaria usually focuses on the feedback dynamics from mosquito to human and back. Early models were based on malaria parasites' population biology and evolution. But increased computing power in recent years has allowed models for the disease to become more detailed and complex.

Mathematical models that study transmission of malaria are based on the "reproduction number," which defines the most important aspects of transmission for any infectious disease. Specifically, it is calculated by determining the expected number of infected organisms that can trace their infection directly back to a single organism after one disease generation. The solution to controlling the disease is to arrive at a reproduction number at which the disease-free state can be established and maintained.

Previous studies used ordinary differential equations to model the transmission of malaria, in which human populations are classified as susceptible, exposed, infectious and recovered. Likewise, mosquito populations are divided into susceptible, exposed and infectious groups. The threshold below which the disease-free equilibrium can be maintained is determined by varying these parameters.

In order to analyze transmission rates of malaria between regions, multi-patch models are used, where each region is a "patch." These models study how the reproduction number is affected by dispersal or movement of exposed and infectious individuals from region to region.

The authors in this paper model the transmission dynamics of malaria between humans and mosquitoes within a patch, and then go on to examine how population dispersal between patches or regions affects the spread of malaria in a two-patch model.

Here is the original post:
The math of malaria

BACKGROUND

Increasing age and post-menopausal status are associated with decreasing androgen concentrations in females. Women with premature loss of ovarian function, such as primary ovarian insufficiency (POI) or iatrogenic menopause may be at increased risk for diminished testosterone levels at a relatively young age. Differentiation between a hypoandrogenic or normoandrogenic state in women with premature loss of ovarian function is problematic due to trueness and precision problems using various testosterone assays. The current meta-analysis was conducted to evaluate current literature reporting serum total testosterone concentrations under these conditions, including stratification for various testosterone assays.

METHODS

A systematic review and meta-analysis of controlled observational studies were performed. The electronic databases of Pubmed, Embase and the Cochrane Library were systematically searched until October 2011 for comparative studies on total testosterone concentrations in women with spontaneous POI or iatrogenic menopause compared with controls. The literature search, data extraction and critical appraisal, using the Newcastle–Ottawa Scale, were performed by two independent investigators. The effect measure was the weighted mean difference (WMD) with 95% confidence interval (95% CI) in a random effects model.

RESULTS

A total of 206 articles for spontaneous POI and 1358 for iatrogenic menopause were reviewed, of which 9 and 17 papers, respectively, were selected for final analysis. Both groups demonstrated significantly lower total testosterone concentrations compared with controls [WMD (95% CI) –0.38 (–0.55 to –0.22) nmol/l, and –0.29 (–0.39 to –0.18) nmol/l, respectively], but with substantial between-study heterogeneity. Subgroup analysis for assay type was statistically significant for spontaneous POI only. Sensitivity analyses of high-quality studies did not change the results, and resulted in a substantial decrease in heterogeneity in spontaneous POI studies.

CONCLUSIONS

The current meta-analysis demonstrates that total testosterone concentrations are decreased in women with spontaneous POI or iatrogenic menopause. The potential implications of hypoandrogenism in these women remain to be elucidated.

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BACKGROUND

Although several randomized controlled trials (RCTs) have examined the effect of misoprostol prior to hysteroscopy for cervical dilatation, no solid conclusion has been reached. We therefore set out to perform a meta-analysis of RCTs.

METHODS

We searched MEDLINE, the ISI Web of Science and the Cochrane Library to identify RCTs comparing misoprostol versus placebo or control prior to hysteroscopy. No restrictions on language or time were applied. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated for all dichotomous outcomes, whereas mean differences (MDs) and 95% CIs were calculated for continuous outcomes using the Mantel–Haenszel or DerSimonian–Laird model according to the heterogeneity.

RESULTS

Of the initial 141 potentially relevant articles that were retrieved, 21 RCTs involving 1786 patients were included in the meta-analysis. Subgroup analyses were performed according to menopausal status and according to whether diagnostic or operative hysteroscopy was performed. Premenopausal women treated with misoprostol had a significantly lower risk for further cervical dilatation in the diagnostic setting [RR (95% CI): 0.56 (0.34–0.92)] and a significantly lower risk for cervical laceration in the operative setting [RR (95% CI): 0.22 (0.09–0.54)], compared with placebo. In contrast, post-menopausal patients did not experience any clear benefit from misoprostol compared with placebo regarding the need for further cervical dilatation [RR (95% CI): 0.99 (0.76–1.30)] and the cervical laceration rate [RR (95% CI): 1.15 (0.40–3.29)]. In addition, the mean cervical width prior to hysteroscopy was significantly higher in premenopausal women treated with misoprostol compared with placebo [MD (95% CI): 2.47 mm (1.81–3.13)] but did not differ among post-menopausal patients [MD (95% CI): 0.39 mm (–0.42 to 1.21)].

CONCLUSIONS

Misoprostol prior to hysteroscopy appears to facilitate an easier and uncomplicated procedure only in premenopausal women.

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http://humupd.oxfordjournals.org/rss/current.xml

BACKGROUND

Uterine adenomyosis was initially thought to be found only in parous women, and final diagnosis was made at histology after hysterectomy. With better imaging techniques and with women attending clinics at older ages, adenomyosis is diagnosed with increasing frequency in women attending infertility clinics. A dozen conservative interventions have been advocated, with variable reports of their impact on fertility. This presents a dilemma for clinicians managing such patients. Hence, this systematic review of adenomyosis was performed to determine (i) the prevalence in a subfertile population, (ii) the accuracy of diagnostic tests, (iii) the efficacy of fertility sparing treatment options and (iv) the reproductive and obstetric/perinatal outcomes in women with adenomyosis.

METHODS

Systematic searches of various databases were performed independently by two reviewers, and data were extracted according to predefined criteria by two reviewers.

RESULTS

There is little data on the epidemiology of adenomyosis associated with subfertility. Both magnetic resonance imaging and ultrasound are non-invasive tests with equivalent accuracy in diagnosing adenomyosis (area under curve 0.91 and 0.88, respectively). Most studies on treatments have been uncontrolled and outcomes are usually reported in the form of case series. Hence, the true impact of various treatments on fertility is not known. There are variable reports of the impact of adenomyosis on the success of IVF. Increased incidence of preterm labour and premature rupture of membranes has been reported in women with adenomyosis.

CONCLUSIONS

Further studies are needed to determine the natural history of adenomyosis and implications for fertility and reproductive outcomes, with and without treatment. Currently, there is no evidence that we should find and treat adenomyosis in patients who wish to conceive.

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http://humupd.oxfordjournals.org/rss/current.xml

BACKGROUND

Thyroid disorders are associated with pregnancy complications. Universal screening is currently not recommended because of a lack of evidence on the effectiveness of treatment. Women with hyperthyroidism and hypothyroidism evidently require treatment but this is less clear for women with subclinical hypothyroidism and thyroid autoimmunity. Therefore, we conducted a systematic review to provide a comprehensive overview on the available treatment interventions.

METHODS

Relevant studies were identified by searching Medline, EMBASE and Cochrane Controlled Trials Register, published until December 2011.

RESULTS

From a total of 7334 primary selected titles, 22 articles were included for the systematic review and 11 were appropriate for meta-analyses. Eight studies reported on hyperthyroidism. Propylthiouracil (PTU) and methimazole reduce the risk for preterm delivery [risk ratio (RR): 0.23, confidence interval (CI): 0.1–0.52], pre-eclampsia (RR: 0.23, CI: 0.06–0.89) and low birthweight (RR: 0.38, CI: 0.22–0.66). The nine studies that reported on clinical hypothyroidism showed that levothyroxine is effective in reducing the risk for miscarriage (RR: 0.19, CI: 0.08–0.39) and preterm delivery (RR: 0.41, CI: 0.24–0.68). For treatment of subclinical hypothyroidism, current evidence is insufficient. The five studies available on thyroid autoimmunity showed a not significant reduction in miscarriage (RR: 0.58, CI: 0.32–1.06), but significant reduction in preterm birth by treatment with levothyoxine (RR: 0.31, CI: 0.11–0.90).

CONCLUSION

For hyperthyroidism, methimazole and PTU are effective in preventing pregnancy complications. For clinical hypothyroidism, treatment with levothyroxine is recommended. For subclinical hypothyroidism and thyroid autoimmunity, evidence is insufficient to recommend treatment with levothyroxine. The overall lack of evidence precludes a recommendation for universal screening and is only justified in a research setting.

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http://humupd.oxfordjournals.org/rss/current.xml